Signal pass-through holes are annularly plated with a conductive material, e.g. copper, to form vias for connecting a first with another set of two identical signal net signatures in a printed circuit board (PCB). As PCB signal routing density increases, so does the spacing density of such vias. With increased density, the vias typically get smaller, which changes their electrical characteristics such as high- and low-frequency signal conductivity, impedance characteristics, etc. Some such vias form connections to signal grounding planes clad within one or more laminar PCB interior surfaces or one or more outer surfaces thereof, and provide for a common ground reference for plural separate signals conveyed by other vias also extending at least partway through the PCB.
Conventionally, an intermediate PCB is provided between a test board and an integrated circuit for temporarily mating the two. Most such intermediate PCBs require soldering of a multi-contact connector array to one or both sides of the intermediate PCB. Problems with such an intermediate PCB include the fact that a PCB's laminar structure including often large clad land areas representing signal routes and/or ground and/or power planes and/or the connector array itself tends to act as a heat-sink (characterized by having a relatively high thermal resistance) during the required soldering step. This either requires higher solder bath temperatures than are desired in manufacture or results in so-called cold solder joints or otherwise unreliable electrical mating characteristics in use. Indeed, the extra interconnect even if improbably but completely formed by soldering nevertheless adds a level of interconnection and thus reduces through-signal integrity and reliability.
Typically, so-called “pogo” pins, coil- and C-spring (or another form of leaf spring) probes, or other suitably compliant contacts are maintained in suitable compression (to ensure a reliable electrical/physical connection) between the via pads on the opposing surfaces of the intermediate PCB and the corresponding pads of the test board and processor mounted typically above and below the intermediate PCB. Exemplary ones of such pogo pins and spring probes are described in High Performance Spring Probe Connector and Test Socket Solutions at http://www.ardentconcepts.com/RC.html (2010) and in Land Grid Array Socket System at http://www.lgasockets.com/desc/defaultt.htm (2008). Familiarity by those of skill in the art with such prior art compliant contact systems is assumed.
In the very remotely related data/video transmission field, coaxial cables conventionally are used in long-distance, high-frequency signal conveyance applications such as video or other high-bandwidth data transmission between remote devices. Such cables typically include a flexible central conductor such as a copper wire, a flexible annular insulator, and a flexible annular outer shield including thin braided or woven conductors. Coaxial cables typically have threaded fasteners on either end for forming a suitably variable length connection between data communication equipment (DCE) and/or data terminal equipment (DTE), e.g. between a computer and a router, a digital video recorder (DVR) and a television (TV), a cable port and a cable modem, a video generator and a video monitor, etc.
Recently, coaxial cable launches have been designed for low-profile electronic circuit board mounting, with discrete solder connections at each coaxial wire-pair terminus. Such is described in U.S. Pat. No. 6,857,898 B2 entitled APPARATUS AND METHOD FOR LOW-PROFILE MOUNTING OF A MULTI-CONDUCTOR COAXIAL CABLE LAUNCH TO AN ELECTRONIC CIRCUIT BOARD, issued Feb. 22, 2005. This recent patent is commonly owned by the assignee of the present invention. The patent teaches the use of conventional flexible coaxial cable wires extending within a flexible ribbon cable featuring conventionally soldered connections for low-profile input/output (I/O) signal routing. The electronic circuit board is routed to thin its terminal edge, thereby creating a pocket or recess to receive the cable wires.